About Offer Stats
The stats we collect are only related to activity on offers, not your store as a whole. So the app shows you how many times the offers were shown to your customers, and how many times the offers were clicked by your customers.
We don't track offers all the way through to conversion because your cart setup, shipping rates, newsletter preferences, and other apps can all have an impact on that. We provide the view and click data for the offers so that they can be optimized as their own step in the checkout funnel - independent of the other parts of the customer flow.
Dollars Added To Cart is a sum of the number of times each offer has been accepted times the value of that offer. It may differ from your sales numbers for a couple of reasons, including test clicks from you or your store staff or abandoned shopping carts. This report gives you the most accurate picture of how your offers are performing, isolated from side effects like changes in shipping rates or cart abandonment. If you find the numbers consistently differ from your sales reports, consider adjusting your Abandoned Cart emails (accessible through your Shopify admin).
In Cart Upsell collects statistics about your offers in near-real time. Normally this data will update itself every ten minutes or so, but you can always fore an update by clicking the "Refresh Stats" button